System for optically monitoring operating conditions in a sample analyzing apparatus

ABSTRACT

A sample analyzing apparatus for performing an optical-based measurement on a sample includes a housing, a first light source, excitation optics, a first light detector, emission optics, and a monitoring system, all of which are disposed in the housing. The monitoring system is configured for monitoring a movable component disposed in the housing. The monitoring system includes one or more light sources for illuminating the movable component, and one or more light detectors for detecting light reflected from the movable component in response to being illuminated.

TECHNICAL FIELD

The present invention generally relates to systems, apparatuses, andmethods for optical-based monitoring of various operating conditionsinternal to a sample analyzing apparatus. The sample analyzing apparatusmay be one that carries out one or more types of optical-basedmeasurements or analyses of samples, such as fluorescence-based,absorbance-based, and/or luminescence-based measurements, and/ormicroscopic imaging.

BACKGROUND

Various analytical instruments have been developed for makingoptics-based measurements (e.g., fluorescence, luminescence, absorbance,microscopy, etc.) on samples (e.g., chemical compounds, biologicalmaterial, etc.) as part of assays useful in the life science industry.Many analytical instruments are designed to carry out only one or a fewdedicated types of measurements. On the other hand, multimode analyticalinstruments, also referred to as multimode readers, are designed toperform multiple analytical assays in a single instrument. Multimodeanalytical instruments may be designed to be re-configurable to enable auser to select different types of measurements to be performed. Somemultimode analytical instruments utilize application-specific cartridgesto enable re-configuration. The samples analyzed or measured by ananalytical instrument typically supported in a multi-well microtiterplate (also known as microplate or optical plate), although other typesof sample holders or containers may be utilized. The microplatecontaining the samples is typically loaded into the interior of theanalytical instrument, and the interior is isolated from the ambient toenable optical-based measurement or imaging to be performed.

Depending on the type(s) of analysis an analytical instrument is capableof performing on a sample, the analytical instrument may include varioustypes of movable components, such as fluidic components (e.g., nozzles,pipettes, etc.), optical components (e.g., lenses, etc.), and mechanicalcomponents (e.g., motorized stages, microtiter plate transports, etc.)that operate in the closed interior of the analytical instrument. Itwould be desirable to be able to monitor these movable components,including determining the presence and position of such components.

SUMMARY

To address the foregoing problems, in whole or in part, and/or otherproblems that may have been observed by persons skilled in the art, thepresent disclosure provides methods, processes, systems, apparatus,instruments, and/or devices, as described by way of example inimplementations set forth below.

According to an embodiment, a sample analyzing apparatus for performingan optical-based measurement on a sample includes: a housing; a firstlight source disposed in the housing and configured for generatingexcitation light; excitation optics disposed in the housing andconfigured for directing the excitation light from the first lightsource to the sample, wherein the sample emits emission light inresponse to being irradiated by the excitation light; a first lightdetector disposed in the housing and configured for measuring theemission light; emission optics disposed in the housing and configuredfor directing the emission light from the sample to the first lightdetector; and a monitoring system configured for monitoring a movablecomponent disposed in the housing, the monitoring system including: asecond light source disposed in the housing and configured forilluminating the movable component; and a second light detector disposedin the housing and configured for detecting light reflected from themovable component in response to being illuminated.

According to another embodiment, a method is provided for monitoring amovable component of a sample analyzing apparatus. The sample analyzingapparatus includes a housing in which the movable component is disposed,a first light source disposed in the housing and configured forgenerating excitation light, excitation optics disposed in the housingand configured for directing the excitation light from the first lightsource to a sample disposed in the housing, a first light detectordisposed in the housing and configured for measuring emission lightemitted from the sample in response to being irradiated by theexcitation light, and emission optics disposed in the housing andconfigured for directing the emission light from the sample to the firstlight detector. The method includes: operating a monitoring system tomonitor the movable component by: operating a second light sourcedisposed in the housing to illuminate the movable component; andoperating a second light detector disposed in the housing detect lightreflected from the movable component in response to being illuminated.

Other devices, apparatuses, systems, methods, features and advantages ofthe invention will be or will become apparent to one with skill in theart upon examination of the following figures and detailed description.It is intended that all such additional systems, methods, features andadvantages be included within this description, be within the scope ofthe invention, and be protected by the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be better understood by referring to the followingfigures. The components in the figures are not necessarily to scale,emphasis instead being placed upon illustrating the principles of theinvention. In the figures, like reference numerals designatecorresponding parts throughout the different views.

FIG. 1 is a schematic view of an example of a sample analyzing apparatusaccording to an embodiment.

FIG. 2 is another schematic view of the sample analyzing apparatus.

FIG. 3 is a perspective view of an example of a microplate and a platelid that may be utilized in a sample analyzing apparatus such asillustrated in FIGS. 1 and 2, according to an embodiment.

FIG. 4 is a perspective view of a monitoring system that may be includedwith a sample analyzing apparatus such as illustrated in FIGS. 1 and 2,according to an embodiment.

DETAILED DESCRIPTION

As used herein, the term “analyte” generally refers to a substance to bedetected or measured by an optical-based technique. Examples of analytesinclude, but are not limited to, proteins (including membrane-boundproteins), antigenic substances, haptens, antibodies, toxins, organiccompounds, peptides, microorganisms, amino acids, nucleic acids,hormones, steroids, vitamins, drugs (including those administered fortherapeutic purposes as well as those administered for illicitpurposes), drug intermediaries or byproducts, bacteria, virus particlesand metabolites of or antibodies to any of the foregoing (asapplicable), and combinations of two or more of any of the foregoing.

As used herein, the term “sample” generally refers to a material knownor suspected of containing the analyte. In implementing the subjectmatter disclosed herein, the sample may be utilized directly as obtainedfrom the source or following a pretreatment to modify the character ofthe sample. The sample may be derived from any biological source, suchas a physiological fluid, including for example blood, interstitialfluid, saliva, ocular lens fluid, cerebral spinal fluid, sweat, urine,milk, ascites fluid, raucous, synovial fluid, peritoneal fluid, vaginalfluid, amniotic fluid or the like. The sample may be pretreated prior touse, such as preparing plasma from blood, diluting viscous fluids, andthe like. Methods of pretreatment can involve filtration, precipitation,dilution, distillation, concentration, inactivation of interferingcomponents, chromatography, separation steps, and the addition ofreagents. Besides physiological fluids, other liquid samples may be usedsuch as water, food products and the like for the performance ofenvironmental or food production assays. In addition, a solid materialknown or suspected of containing the analyte may be used as the sample.In some instances it may be beneficial to modify a solid sample to forma liquid medium or to release the analyte from the solid sample.

As used herein, the term “light” generally refers to electromagneticradiation, quantizable as photons. As it pertains to the presentdisclosure, light may propagate at wavelengths ranging from ultraviolet(UV) to infrared (IR). In the present disclosure, the term “light” isnot intended to be limited to electromagnetic radiation in the visiblerange. In the present disclosure, the terms “light,” “photons,” and“radiation” are used interchangeably.

As used herein, in relation to the detection or measurement of opticalsignals emanating from a sample, terms such as “emission light” or“emitted light” refer to light emitted from the sample as a consequenceof fluorescence or luminescence. Additionally, for convenience termssuch as “emission light” or “emitted light” also refer to light that istransmitted through a sample and collected for the purpose of measuringabsorbance.

FIG. 1 is a schematic view of an example of a sample analyzing apparatus100 according to some embodiments. In FIG. 1, the various components ofthe sample analyzing apparatus 100 are schematically arranged generallyin the overall direction of light transmission from one component toanother component. FIG. 2 is another schematic view of the sampleanalyzing apparatus 100. FIG. 2 may generally be taken to be anelevation view, with the understanding that the components generallyhave been arranged in an arbitrary manner. In actual embodiments, therelative positions of the components to each other may differsignificantly from what is schematically depicted or suggested in FIGS.1 and 2.

The sample analyzing apparatus 100 is configured for performing one ormore types of optical-based measurements on a sample (or on multiplesamples) to detect or measure analytes of interest. In some embodiments,the sample analyzing apparatus 100 is configured to enable a user toselect a desired type of optical measurement to be performed, such asmeasurements based on fluorescence, absorbance, luminescence, cellimaging, etc. For example, the user may be able to reconfigure theoptics of the sample analyzing apparatus 100 to perform a desired typeof optical measurement. Thus, in some embodiments the sample analyzingapparatus 100 may be a multi-mode reader. For example, as a multi-modereader the sample analyzing apparatus 100 may be reconfigurable byenabling a user to select an application-specific cartridge among anumber of different cartridges available, and load the selectedcartridge into the sample analyzing apparatus 100 so as to establishoptical and electrical circuits specific to the desired application. Inthis manner, the selected cartridge may be operatively coupled to thesample analyzing apparatus 100 whereby the sample analyzing apparatus100 is properly configured for carrying out the selected experiment.Each cartridge may contain internal optics specific to or optimized fora particular type of experiment (e.g., fluorescence, absorbance,luminescence, etc.). The internal optics housed within the cartridge maycommunicate with external optics housed within the housing of the sampleanalyzing apparatus 100 through optical ports of the cartridge'shousing. Some cartridges may additionally include one or more internallight sources and/or one or more internal light detectors. The sampleanalyzing apparatus 100 may be configured to receive and support morethan one cartridge at the same time, and a particular cartridge maythereafter be selected for coupling into the optical path defined by thesample analyzing apparatus 100, such as by moving the selected cartridgeto an operative position in the interior of the sample analyzingapparatus 100. Examples of cartridge-based multi-mode readers aredescribed in U.S. Pat. Nos. 9,188,527 and 8,119,066, the contents ofwhich are incorporated by reference herein in their entireties.

Generally, the structure and operation of the various componentsprovided in optical-based sample analysis instruments are understood bypersons skilled in the art, and thus are only briefly described hereinto facilitate an understanding of the presently disclosed subjectmatter. In the illustrated embodiment, the sample analyzing apparatus100 includes a sample carrier 104 configured for supporting one or moresamples under analysis, a light source 108 for generating excitationlight, a light detector 112 for receiving and measuring emission lightpropagating from the sample (e.g., by fluorescence or luminescence),excitation optics 116 configured for directing the excitation lightalong an excitation light path from the light source 108 to the sampleand processing or modifying the excitation light in one or more ways,and emission optics 120 configured for directing emission light along anemission light path from the sample (e.g., emitted by the sample byfluorescence or luminescence) to the light detector 112 and processingor modifying the excitation light in one or more ways. When configuredas a multi-mode reader, the sample analyzing apparatus 100 may furtherinclude a cartridge module 124 configured to removably receive andsupport and plurality of application-specific cartridges configured forimplementing specific optics-based measurements (e.g., fluorescence,absorbance, luminescence, etc.) as described above, and intermediate orinterface optics 126 configured for providing optical interfaces betweena selected cartridge and the excitation optics 116 and emission optics120. The sample analyzing apparatus 100 further includes an apparatushousing 128 that encloses the sample carrier 104 and cartridge module124 (when in operative positions for carrying out optical measurementson the sample), as well as other components of the sample analyzingapparatus 100 such as the light source 108, light detector 112,excitation optics 116, and emission optics 120. The apparatus housing128 may include one or more panels, doors, drawers, etc. for allowingaccess to interior regions of the sample analyzing apparatus 100,including for loading samples onto the sample carrier 104 and cartridgesinto the cartridge module 124. The sample analyzing apparatus 100 mayfurther include an incubation chamber 130 (FIG. 2) in the apparatushousing 128, at which the sample(s) (supported on the sample carrier104) may be operatively located.

Generally, the sample carrier 104 is configured for moving one or moresamples along one or more axes. For example, the sample carrier 104 maybe an X-Y stage movable in two dimensions in a horizontal plane,although in other embodiments may also be movable in a third vertical(Z) dimension. The sample carrier 104 may be a manually actuated,semi-automated, or fully-automated (motorized) stage or platform. Intypical embodiments, one or more samples are supported or held by asuitable sample support 106 (FIG. 2), which is in turn supported by thesample carrier 104. Generally, the sample support 106 may be one or morecontainers configured for holding one or more samples during ananalysis. As non-limiting examples, the sample support 106 may be amulti-well plate (also known as a microtiter plate, microplate, oroptical plate), one or more cuvettes or vials, a substrate supportingspots or blots containing respective samples, etc. The sample carrier104 may be movable into and out from the apparatus housing 128. Thus asample, or sample support 106 that supports one or more samples, may bemounted onto the sample carrier 104 while the sample carrier 104 is atan outside position, e.g., where the sample carrier 104 is positioned atleast partially outside the apparatus housing 128. The sample carrier104 may then be moved to an inside position at which the sample carrier104 is positioned entirely in the apparatus housing 128 (as illustratedin FIG. 1) so as to align the sample (or successively align multiplesamples) with one or more optical components of the sample analyzingapparatus 100.

The light source 108 is utilized in embodiments requiring excitation(irradiation) of the sample, such as fluorescence and absorbancedetection techniques. In some embodiments, the light source 108 is abroadband light source such as a flash lamp (e.g., a xenon flash lamp,deuterium flash lamp, halogen flash lamp, metal halide flash lamp,etc.), which may be configured to produce a pulsed light beam. In otherembodiments, other light sources such as light emitting diodes (LEDs),laser diodes (LDs), lasers, etc. may be provided, and the sampleanalyzing apparatus 100 may be configured to enable switching betweendifferent types of light sources, as appreciated by persons skilled inthe art.

Generally, the excitation optics 116 may include, for example, one ormore lenses, apertures, filters, light guides (e.g., optical fibers),mirrors, beam splitters, monochromators, diffraction gratings, prisms,optical path switches, etc. In the present embodiment, the excitationoptics 116 may include an excitation monochromator 132 and/or anexcitation filter holder 136. As appreciated by persons skilled in theart, the excitation monochromator 132 and the excitation filter holder136 both function as wavelength selectors for controlling the specificwavelength (or narrow band of wavelengths) of the excitation light to bepassed further through the optical system. That is, the excitationmonochromator 132 and the excitation filter holder 136 both function toreceive the excitation light from the light source 108 and transmit theexcitation light onwards at a desired wavelength or narrow band ofwavelengths (colors), but operate on different principles.

The excitation monochromator 132 comprises one or more diffractiongratings that spatially separate the different wavelengths of theexcitation light. The excitation monochromator 132 transmits thecomponent of the excitation light having a selected wavelength byrotating the diffraction grating(s) to a position that aligns theexcitation light having the selected wavelength with an exit slit. Allcomponents of the excitation light having non-selected wavelengths arenot aligned with the exit slit, and thus are blocked from propagating inthe optical path beyond the excitation monochromator 132.

On the other hand, the excitation filter holder 136 supports a pluralityof optical filters composed of materials having different opticaltransmission characteristics. That is, the optical filters areformulated to pass different wavelengths of the excitation light. Theexcitation filter holder 136 is configured so as to be movable, eitherby rotation or (in the illustrated embodiment) linear translation (i.e.,sliding). Hence, the excitation filter holder 136 may be actuated so asto move a selected filter into the optical path, whereby the selectedfilter allows passage of only the selected wavelength (or narrow band ofwavelengths) onward in the optical path beyond the excitation filterholder 136, while blocking all other wavelengths. In one embodiment theexcitation filter holder 136 comprises eight positions, including up tosix positions occupied by optical filters (e.g., long pass, short pass,band pass, etc.), another position being an open aperture through whichthe excitation light can pass without any interference, and anotherposition presenting a material that blocks the excitation lightcompletely.

In an embodiment including both the excitation monochromator 132 and theexcitation filter holder 136, the optical path provided for excitationlight to be transmitted from the light source 108 to the excitationfilter holder 136 may be split into a first excitation light path 140and a second excitation light path 144. As schematically illustrated inFIG. 1, the excitation monochromator 132 is in (i.e., opticallycommunicates with, or operates in) the first excitation light path 140only. Thus, the first excitation light path 140 directs excitation lightfrom the light source 108, through the excitation monochromator 132,through the selected excitation filter of the excitation filter holder136, and onward to the sample (appropriately positioned at the samplecarrier 104). The second excitation light path 144 directs excitationlight from the light source 108, through the selected excitation filterof the excitation filter holder 136, and to the sample while bypassingthe excitation monochromator 132. In the illustrated embodiment, thesample analyzing apparatus 100 is configured for switching the opticalpath between the first excitation light path 140 and the secondexcitation light path 144. In other words, the sample analyzingapparatus 100 is configured for selecting whether the excitation lightgenerated by the light source 108 is directed through the firstexcitation light path 140 or through the second excitation light path144, and thereby selects whether or not the excitation monochromator 132is bypassed. For this purpose, the excitation optics 116 include anexcitation path selection device 148. As described further below, theexcitation path selection device 148 is movable (can be actuated tomove) so as to direct the excitation light from the light source 108into either the first excitation light path 140 or the second excitationlight path 144. As will also become evident, the excitation pathselection device 148 may comprise only a single movable component, i.e.,only a single movable component is needed to guide the excitation lightinto the selected (first or second) excitation light path 140 or 144.

As also illustrated in FIG. 1, in some embodiments the excitation optics116 may further include an additional optics holder 152 that holds aplurality of different optics components. The additional optics holder152 is movable (by rotation or sliding) so as to insert a selectedoptics component into the first excitation light path 140 between theexcitation monochromator 132 and the excitation filter holder 136, andinto the second excitation light path 144 between the light source 108and the excitation filter holder 136. The additional optics holder 152may include one or more attenuation filters providing differentattenuation factors (e.g., no attenuation, 10D, 20D, 30D, etc.) toreduce the energy of the excitation light in the event that samples witha high response are measured that would saturate the light detector 112.A reference beam splitter (not shown) following the additional opticsholder 152 may split off a portion of the excitation light beam as areference beam that is directed to a reference photodiode (note shown).The reference photodiode may be utilized to track the energy of theexcitation light. Based on the intensity of the excitation lightmeasured by the reference photodiode, a system controller (computingdevice) 190 (FIG. 2) of the sample analyzing apparatus 100 may attenuatethe excitation light by actuating the additional optics holder 152 tomove so as to insert an attenuation filter of a selected attenuationfactor into the active excitation light path 140 or 144. Such techniqueof dynamic range extension may be implemented as described in U.S.Patent Application Publication No. U.S. 2013/0119277, the entirecontents of which are incorporated by reference herein. In addition oras an alternative to attenuation filters, other examples of opticscomponents that may be positioned at the additional optics holder 152include, but are not limited to, beam-shaping apertures, open apertures(i.e., apertures that do not attenuate or modify the light beam passingtherethrough), and filters with specialized functions (e.g., long pass,short pass, band pass, etc.).

Generally, the emission optics 120 may include, for example, one or morelenses, apertures, filters, light guides (e.g., optical fibers),mirrors, beam splitters, monochromators, diffraction gratings, prisms,optical path switches, etc. In the present embodiment, the emissionoptics 120 may include an emission monochromator 156 and/or an emissionfilter holder 160. The emission filter holder 160 may support aplurality of emission filters having different light transmissioncharacteristics. The emission monochromator 156 and the emission filterholder 160 may generally be similar to the excitation monochromator 132and the excitation filter holder 136 described herein, and may beoptimized as needed for use in the emission light path.

In an embodiment including both the emission monochromator 156 and theemission filter holder 160, the optical path provided for emission lightto be transmitted from the sample (or intervening cartridge and/orinterface optics 126, depending on the measurement technique beingimplemented) to the light detector 112 may be split into a firstemission light path 164 and a second emission light path 168. Asschematically illustrated in FIG. 1, the emission monochromator 156 isin (i.e., optically communicates with, or operates in) the firstemission light path 164 only. Thus, the first emission light path 164directs emission light through the emission monochromator 156, throughthe selected emission filter of the emission filter holder 160, andonward to the light detector 112. The second emission light path 168directs emission light through the selected emission filter of theemission filter holder 160, and to the light detector 112 whilebypassing the emission monochromator 156. In the illustrated embodiment,the sample analyzing apparatus 100 is configured for switching theemission light path between the first emission light path 164 and thesecond emission light path 168. In other words, the sample analyzingapparatus 100 is configured for selecting whether or not the emissionmonochromator 156 is bypassed. In the present embodiment, the interfaceoptics 126 include a main optical path selection device 172 configuredfor switching between the first emission light path 164 and the secondemission light path 168.

Generally, the light detector 112 is configured to generate electricalmeasurement signals in response to receiving emission light signals fromthe emission optics 120, and transmit the measurement signals to signalprocessing circuitry (e.g., data acquisition circuitry) provided with orexternal to the sample analyzing apparatus 100 (e.g., as generallyrepresented by a system controller 190, described below). Depending onthe embodiment, the light detector 112 may be a photomultiplier tube(PMT), a photodiode, a charge-coupled device (CCD), an active-pixelsensor (APS) such as a complementary metal-oxide-semiconductor (CMOS)device, etc., as needed to optimize sensitivity to the emissionwavelengths to be detected. In a typical embodiment, the illustratedlight detector 112 comprises one or more PMTs optimized for processingfluorescence and/or luminescence emission light signals. A separatelight detector (not shown in FIGS. 1 and 2) optimized for processingabsorbance emission light signals, such as a photodiode, may beprovided.

As described above, the cartridge module 124 is configured to removablyreceive and support and plurality of application-specific cartridgesconfigured for implementing specific optics-based measurements (e.g.,fluorescence, absorbance, luminescence, cell imaging, etc.). For thispurpose, the cartridge module 124 may include a plurality of receptaclesor slots into which individual cartridges may be installed (loaded) andthereafter uninstalled (removed). The cartridge module 124 may bemovable in an automated, semi-automated, or manual manner. For example,the cartridge module 124 may be movable through a door of the apparatushousing 128 to an at least partially outside position that facilitatesinstallation and uninstallation of cartridges. As another example, thecartridge module 124 may be movable within the interior of the apparatushousing 128 to enable a selected cartridge to be optically aligned withthe optical system of the sample analyzing apparatus 100 (i.e., placedin optical communication with the excitation optics 116 and emissionoptics 120). Depending on the type of experiment for which a givencartridge is utilized, the internal optics enclosed by the cartridgehousing of the cartridge may include various components such as, forexample, mirrors, filters, prisms, diffraction gratings, internal lightsources, and/or internal light detectors.

Generally, the interface optics 126 may include, for example, one ormore lenses, optical read heads, apertures, filters, light guides (e.g.,optical fibers), mirrors, beam splitters, optical path switches, etc. Inthe present embodiment, the interface optics 126 include the mainoptical path selection device 172. In addition to being configured toswitch between the first emission light path 164 and the second emissionlight path 168, the main optical path selection device 172 may beconfigured to select a measurement method by selecting appropriateoptical paths between the excitation optics 116 and the sample, andbetween the sample and the emission optics 120. The main optical pathselection device 172 may also be configured to select whether thecartridge module 124 (i.e., a specific cartridge installed in thecartridge module 124) is placed in optical communication with (isinserted into) the optical path (excitation light path and/or emissionlight path). For these purposes, the main optical path selection device172 may include a structural body at which various optical componentsare mounted, attached, or formed, such as, for example, one or morelenses, apertures, light guides (e.g., optical fibers), mirrors, beamsplitters, etc. The structural body of the main optical path selectiondevice 172 may provide a plurality of selectable positions, and may bemovable (e.g., slidable) to select which position is to be the operableor active position in the optical path.

As illustrated in FIG. 2, the interface optics 126 may further include atop absorbance lens 176 (a lens utilized for absorbance measurements)positioned above the sample carrier 104 (in alignment with a selectedsample supported on the sample carrier 104), a topfluorescence/luminescence lens 180 (a lens utilized for fluorescence andluminescence measurements) positioned above the sample carrier 104 (inalignment with a selected sample supported on the sample carrier 104), abottom absorbance read head 184 positioned below the sample carrier 104(in alignment with a selected sample supported on the sample carrier104), and a bottom fluorescence read head 188 positioned below thesample carrier 104 (in alignment with a selected sample supported on thesample carrier 104). In some embodiments, the topfluorescence/luminescence lens 180 may be movable toward and away fromthe sample to accommodate different multi-well plate sizes, fillvolumes, sample heights, etc., and to avoid cross-talk among neighboringwells of the multi-well plate.

The selection of a measurement method may entail operating theexcitation path selection device 148 to select the first excitationlight path 140 or the second excitation light path 144 as describedherein, in conjunction with operating the main optical path selectiondevice 172 to select a position. The main optical path selection device172 may also be configured to select whether the emission light istransmitted through the emission monochromator 164 or through theemission filter holder 160. As one non-limiting example, the mainoptical path selection device 172 may provide the following selectablepositions:

One or more positions utilized to couple an application-specificcartridge of the cartridge module 124 into the optical path to provideextended system capabilities, such as time-resolved fluorescence,multiplexed time-resolved fluorescence, fluorescence polarization,ALPHASCREEN® assays, NANO-TRF® assays, etc.

One or more positions utilized for absorbance measurements inconjunction with a selected combination of excitation and/or emissionwavelength selectors (e.g., excitation monochromator 132, excitationfilter holder 136, emission monochromator 164, and/or emission filterholder 160). The excitation light beam is directed to the top absorbancelens 176. The top absorbance lens 176 is a focusing lens that collimatesthe excitation light beam such that the focal point of the beam is inthe center of the sample. The emission light (in this case, the lighttransmitted through the sample) is collected by the bottom absorbanceread head 184. The transmitted light may then be directed to anabsorbance-specific light detector (e.g., a photodiode, not shown inFIG. 1).

One or more positions utilized for luminescence measurements inconjunction with the emission monochromator 164 and/or emission filterholder 160. As appreciated by persons skilled in the art, luminescencemeasurements do not utilize excitation light, but rather luminescence isinitiated by adding an appropriate reagent to the sample. Luminescentemission light from the sample is collected by the topfluorescence/luminescence lens 180, and is directed through the emissionoptics 120 to the light detector 112.

One or more positions utilized for bottom-read fluorescence measurementsin conjunction with a selected combination of excitation and/or emissionwavelength selectors (e.g., excitation monochromator 132, excitationfilter holder 136, emission monochromator 164, and/or emission filterholder 160). The excitation light is directed via an excitation opticalfiber (not shown) to the bottom fluorescence read head 188, whichfocuses the excitation light beam on the sample (thereby irradiating thesample from the bottom of the multi-well plate). The emission light (inthis case, the fluorescence light emitted from the sample) is collectedby the bottom fluorescence read head 188. The emission light may then bedirected to main optical path selection device 172 via an emissionoptical fiber (not shown), and then onward through the emission optics120 to the light detector 112.

One or more positions utilized for top-read fluorescence measurements inconjunction with the excitation monochromator 132 and the emissionmonochromator 164, or in conjunction with the excitation filter holder136 and the emission monochromator 164. At this position, the emissionlight is directed to the top fluorescence/luminescence lens 180, whichfocuses the excitation light beam on the sample (thereby irradiating thesample from the top of the multi-well plate). The emission light maythen be collected by the same top fluorescence/luminescence lens 180,and then onward through the emission optics 120 to the light detector112.

One or more positions utilized for microscopy (e.g., cell imaging),which may be fluorescence-based microscopy. At this position, opticalelements defining light paths utilized for microscopy are coupled intothe optical system of the sample analyzing apparatus 100 as needed toilluminate/excite the sample and acquired images from the sample.

Referring to FIG. 2, in some embodiments, the sample analyzing apparatus100 may further include a liquid injecting system. The liquid injectingsystem may include one or more injector nozzle(s) (or needle(s)) 210,and associated fluid conduits (tubing), pump(s), reservoir(s), etc. (notshown) configured for adding a liquid to the sample (e.g., into selectedwells of the sample support 106 or onto selected blots of the samplesupport 106 disposed on the sample carrier 104) before or after thesample has been operatively positioned in the sample analyzing apparatus100. For example, a labeling agent may be added to the sample forfluorescence, luminescence or other types of measurements, asappreciated by persons skilled in the art. In some embodiments, two ormore different types of reagents may be added. As depicted by an arrowin FIG. 2, the injector nozzle 210 may be movable in the verticaldirection (along the z-axis) toward and away from a sample supported onthe sample support 106. For this purpose, the injector nozzle 210 may bemounted to a motorized stage. The motorized stage may also be configuredto move the injector nozzle 210 in horizontal directions (along thex-axis and y-axis) to precisely locate the injector nozzle 210 above aselected sample container (e.g., microplate well or blot) of the samplesupport 106.

In some embodiments, the sample analyzing apparatus 100 may furtherinclude a liquid pipetting system. The liquid pipetting system mayinclude one or more pipette tips 214, and associated fluid conduits(tubing), pump(s), reservoir(s), etc. (not shown), configured fortransporting liquids (e.g., solutions) to and from the sample carrier104, particularly to and from a sample support 106 disposed on thesample carrier 104 before or after the sample support 106 has beenmounted on the sample carrier 104. The liquid pipetting system isfurther configured for dispensing precise amounts of liquid intoselected wells of the sample support 106 (or onto selected blots of thesample support 106 disposed on the sample carrier 104) and/or aspiratingprecise amounts of liquid therefrom, which may be done before or afterthe sample has been operatively positioned in the sample analyzingapparatus 100. As depicted by an arrow in FIG. 2, the pipette tip 214may be movable in the vertical direction (along the z-axis) toward andaway from a sample supported on the sample support 106. For thispurpose, the pipette tip 214 may be mounted to a motorized stage (e.g.,a pipettor head). The motorized stage may also be configured to move thepipette tip 214 in horizontal directions (along the x-axis and y-axis)to precisely locate the pipette tip 214 above a selected samplecontainer (e.g., microplate well or blot) of the sample support 106.

In some embodiments, the sample analyzing apparatus 100 may furtherinclude a microscopy (e.g., cell imaging) system. The microscopy systemmay include an objective lens 218 (or other type of movable opticallens) and associated optics (e.g., other types of lenses, diaphragms,apertures, mirrors, beam splitters, excitation filters, emissionfilters, etc., not shown), and also a light source and a light detector.The microscopy system is configured for establishing an excitation pathfrom the light source to a selected sample supported on the samplecarrier 104 to illuminate the sample (or to excite fluorophores of thesample in the case of fluorescence microscopy), establishing an emissionpath from the sample to the light detector to carry emission lightemitted from the sample (which may be in response to fluorescentexcitation in the case of fluorescence microscopy), and acquiring imagesfrom the sample based on the emission light received by the lightdetector. The light source utilized for the microscopy system maydifferent from the illustrated light source 108 utilized forfluorescence or absorbance measurements. Alternatively, the interfaceoptics 126 (FIG. 1) may be adjustable (e.g., to another position of themain optical path selection device 172) to couple the light beamproduced by the light source 108 into the microscopy system. The lightdetector utilized for the microscopy system may different from theillustrated light detector 112 utilized for fluorescence measurements.The light detector utilized for the microscopy system is typically amulti-pixel light detector such as a camera. Additionally oralternatively, a microscopy-specific cartridge loaded into the cartridgemodule 124 (FIG. 1, if provided) containing some or all of thecomponents of the microscopy system may be utilized.

As depicted by an arrow in FIG. 2, the objective lens 218 may be movablein the vertical direction (along the z-axis) toward and away from asample supported on the sample support 106, for focusing images andscanning the sample through its thickness along the z-axis. For thispurpose, the objective lens 218 may be mounted to a motorized stage. Themotorized stage may also be configured to move the objective lens 218 inhorizontal directions (along the x-axis and y-axis) to precisely locatethe objective lens 218 above a selected sample container (e.g.,microplate well or blot) of the sample support 106.

Referring to FIG. 2, the sample analyzing apparatus 100 may furtherinclude a system controller (e.g., a computing device) 190. Asappreciated by persons skilled in the art, the system controller 190 mayinclude one or more modules configured for controlling, monitoringand/or timing various functional aspects of the sample analyzingapparatus 100, and/or for receiving data or other signals from thesample analyzing apparatus 100 such as measurement signals from thelight detector 112 and transmitting control signals to the lightdetector 112 and/or other components. For example, the system controller190 may be configured for coordinating the operations (e.g., movementsand positions) of the sample carrier 104, the cartridge module 124 (ifprovided), the excitation monochromator 132, the excitation filterholder 136, the excitation path selection device 148, the emissionmonochromator 156, the emission filter holder 160, the main optical pathselection device 172, the injector nozzle 210, the pipette tip 214, andthe objective lens 218. For all such purposes, the system controller 190may communicate with various components of the sample analyzingapparatus 100 via wired or wireless communication links. In typicalembodiments, the system controller 190 includes a main electronicprocessor providing overall control, and may include one or moreelectronic processors configured for dedicated control operations orspecific signal processing tasks. The system controller 190 may alsoinclude one or more memories and/or databases for storing data and/orsoftware. The system controller 190 may also include a computer-readablemedium that includes instructions for performing any of the methodsdisclosed herein. The functional modules of the system controller 190may comprise circuitry or other types of hardware (or firmware),software, or both. For example, the modules may include signalprocessing (or data acquisition) circuitry for receiving measurementsignals from the light detector 112 and software for processing themeasurement signals such as for generating graphical data. The systemcontroller 190 may also include or communicate with one or more types ofuser interface devices, such as user input devices (e.g., keypad, touchscreen, mouse, and the like), user output devices (e.g., display screen,printer, visual indicators or alerts, audible indicators or alerts, andthe like), a graphical user interface (GUI) controlled by software, anddevices for loading media readable by the electronic processor (e.g.,logic instructions embodied in software, data, and the like). The systemcontroller 190 may include an operating system (e.g., Microsoft Windows®software) for controlling and managing various functions of the systemcontroller 190.

FIG. 3 is a perspective view of a microplate 306 that may be utilized inthe sample analyzing apparatus 100 illustrated in FIGS. 1 and 2. Themicroplate 306 may correspond to the sample support 106 illustrated inFIG. 2, and thus may be mounted on the sample carrier 104. Themicroplate 306 includes a two-dimensional array of wells 322 utilized tocontain respective samples to be analyzed. In a typical embodiment, thetwo-dimensional array is a 2:3 rectangular matrix. Typical examplesinclude 96, 384 or 1536 wells 322, although the total number of wells322 may be less than 96 or more than 1536. The wells 322 may bepolygonal (as illustrated) or cylindrical. Depending on the analysis tobe performed, the wells 322 may contain various solutions and reagents.The wells 322 are individually addressable by various optical-relatedcomponents (e.g., the top absorbance lens 176, topfluorescence/luminescence lens 180, bottom absorbance read head 184,bottom fluorescence read head 188, and objective lens 218) and fluidiccomponents (e.g., the injector nozzle 210 and pipette tip 214) describedherein. For optical reading from the bottom of the microplate 306, thewells 322 are optically transparent. Depending on the analysis to beperformed, a plate lid 326 may be mounted to the top of the microplate306 to cover the wells 322. The lid 326 may be opaque to block lightfrom propagating into or out from the top of the microplate 306. The lid326 may be utilized, for example, in conjunction with optical readingfrom the bottom of the microplate 306.

As also illustrated in FIG. 3, the microplate 306 may include one ormore barcode labels 354 on which barcode (e.g., one-dimensional (1D)barcode, two-dimensional (2D) barcode such as QR barcode) is printed.The barcode labels 354 may be provided on one or more sides of themicroplate 306. The barcodes may contain various types of informationsuch as, for example, the identity of the microplate 306 and/or samplescontained in the microplate 306. The barcodes may be read by anappropriate reading device, as appreciated by persons skilled in theart.

According to some embodiments, an experiment entailing opticalmeasurement utilizing the sample analyzing apparatus 100 may beimplemented as follows. The sample or samples are introduced into thesample analyzing apparatus 100 and placed in a proper operating positionrelative to optics and other components of the sample analyzingapparatus 100. Generally, the “operating” position of the sample is an“optically aligned” position, i.e., a position that establishes anoptical path sufficient for optical data acquisition from the sample.Depending on the experiment, the operating position may also correspondto the sample being “fluidly aligned” with the sample analyzingapparatus 100, i.e., positioned so as to be able to dispense fluid ontothe sample such as by operating a liquid injecting system as describedabove, and/or operating a liquid pipetting system to dispense fluid intoand/or aspirate fluid from sample containers or blots of the samplesupport 106. Sample introduction may entail loading one or more samplesin one or more wells of a microplate or other type of sample support 106(e.g., preparing samples in accordance with blotting techniques such asWestern Blot, as appreciated by persons skilled in the art), and loadingor mounting the sample support 106 in the sample analyzing apparatus100, such as with the use of the sample carrier 104 described above.Depending on the sample and the type of measurement to be made, thesample may be subjected to preparation or treatment (incubation, mixing,homogenization, centrifuging, buffering, reagent addition, analyticalseparation such as solid phase extraction, chromatography,electrophoresis, etc.) prior to being positioned in the sample analyzingapparatus 100, as appreciated by persons skilled in the art.

In addition to sample introduction, the sample analyzing apparatus 100or certain components thereof (optics, electronics, etc.) may need to beconfigured for implementing the specific type of measurement to be made.For example, if cartridge-based, the appropriate cartridge (orcartridges) may be installed in the cartridge module 124 of the sampleanalyzing apparatus 100. After installing a cartridge, optics providedin the cartridge become part of the optical circuit within the apparatushousing 128 of the sample analyzing apparatus 100. For example, thecartridge optics may be aligned with (in optical communication with) theexcitation optics 116, emission optics 120, and/or interface optics 126.Installing the cartridge results in establishing electrical paths fortransmitting power, data and control signals to and/or from thecartridge.

The sample is then processed as necessary to induce the emission ofphotons from the sample for measurement. In the case of luminescencemeasurement, reagents may be added to induce a luminescent response,such as by operating a liquid injecting system as described above. Inthe case of fluorescence measurement, the light source 108 andassociated excitation optics 116 (and possibly a cartridge and/or theinterface optics 126, as described above) are utilized to irradiate orexcite the sample to induce a fluorescent response. Fluorescencemeasurement may additionally entail the addition of reagents to inducethe fluorescent response. In the case of either luminescence orfluorescence measurement, the emission optics 120 (and possibly acartridge and/or the interface optics 126, as described above) areutilized to collect the emission light from the sample and direct theemission light to the light detector 112. The light detector 112converts these optical signals into electrical signals (detectorsignals, or measurement signals) and transmits the electrical signals tosignal processing circuitry, such as may be provided by a systemcontroller 190 of the sample analyzing apparatus 100 as described above.

In the case of absorbance measurement, the light source 108 andassociated excitation optics 116 (and possibly a cartridge and/or theinterface optics 126, as described above) are utilized to irradiate thesample. In this case, the “emission” light is the light transmittedthrough the sample, which is attenuated in comparison to the excitationlight incident on the sample due to absorbance by the sample of some ofthe light. The transmitted (“emission”) light may be directed to anabsorbance detector that may be separate from the illustrated lightdetector 112, as described above.

Depending on the embodiment, the method may include operation and/or useof other components of the sample analyzing apparatus 100, such as oneor more cartridges of the cartridge module 124, the interface optics126, the excitation path selection device 148, the excitationmonochromator 132, the excitation filter holder 136, the main opticalpath selection device 172, the emission monochromator 164, the emissionfilter holder 160, etc., all as described elsewhere herein.

For any of the optical measurement techniques implemented, multiplesamples may be processed. For example, the sample support 106 on or inwhich the multiple samples are provided may be moved (such as by usingthe sample carrier 104) to sequentially align each sample with theoptics being utilized for the experiment, whereby measurements are takenfrom all samples sequentially.

Referring to FIG. 2, in some embodiments, the sample analyzing apparatus100 may further include an optical-based monitoring system 350configured to monitor one or more operating conditions (or states)present in the interior enclosed by the apparatus housing 128 of thesample analyzing apparatus 100. The monitoring system 350 includes oneor more light sources and one or more light detectors. The lightsource(s) are positioned to illuminate region(s) or surface(s) in theinterior of the sample analyzing apparatus 100 at which monitoring isdesired by the light detector(s). Depending on the particular operatingcondition or state being monitored, a given light detector may beconfigured to make an optical-based measurement or to acquire imagesviewable by a user in real time. The light sources utilized in themonitoring system 350 are typically LEDs, but more generally may be anyappropriate type of light sources, such as the other examples notedherein. The light detectors utilized in the monitoring system 350 aretypically cameras to enable the capturing of images (still images, orboth still images and video). However, for monitoring functionsinvolving detection or measurement not requiring multi-pixel imaging,another type of light detector may be utilized, such as the otherexamples noted herein.

In the illustrated embodiment, the sample analyzing apparatus 100includes two light sources 330 and 334 and a camera 338 utilized formonitoring. In other embodiments, more than two light sources 330 and334 and more than one may camera 338 be included. The light sources 330and 334 may be positioned and oriented to emit respective light beams342 and 346 in different directions or angles relative to each other. Inthe illustrated embodiment, the light beam 342 is oriented horizontallyand the light beam 346 is oriented vertically, but more generally thelight beams 342 and 346 may be oriented at any angles useful forcarrying out the monitoring functions. The camera 338 may be positionedand oriented to receive light reflected or emitted from surfaces orregions illuminated by the light sources 330 and/or 334, and therebymake optical-based measurements to enable a user to view the illuminatedsurfaces or regions, such as on a display screen communicating with thesystem controller 190.

FIG. 4 is a perspective view of the monitoring system 350. FIG. 4illustrates an example of the positions of the light sources 330 and 334and the camera 338, relative to each other and to other interiorcomponents such as the sample carrier 104 and the objective lens 218.The light sources 330 and 334 and the camera 338 may be mounted toappropriate inside surfaces in the housing 128 of the sample analyzingapparatus 100. The light sources 330 and 334 and the camera 338 maycommunicate with the system controller 190 (FIG. 2) as needed forimplementing the monitoring functions of the monitoring system 350. Forexample, the system controller 190 may transmit control signals to thelight sources 330 and 334 and the camera 338, and the camera 338 maytransmit output signals (measurement signals) to the system controller190 for signal processing as needed for optical-based measurement orimaging. The light sources 330 and 334 and the camera 338 may be mountedto appropriate inside surfaces in the housing 128 of the sampleanalyzing apparatus 100. The light sources 330 and 334 and the camera338 may be mounted to respective printed circuit boards (PCBs)containing electronics. In some embodiments, such PCBs may be consideredas being part of the system controller 190.

Depending the monitoring function(s) to be implemented, the monitoringsystem 350 may operate before, during, or after a sample analysis asdescribed herein is performed, and may operate in one or more iterationsduring such time periods to perform one or more different monitoringfunctions. Notably, the illumination and detecting/imaging functionsimplemented by the monitoring system 350 are completely internal, i.e.,inside the apparatus housing 128. Thus, the operation of the monitoringsystem 350 does not require opening the apparatus housing 128 andexposing sensitive optical components (e.g., the light detector 112) tothe ambient. Examples of monitoring functions, and operating conditionsthat may be monitored by the monitoring system 350, include, but are notlimited to, the following.

Plate presence detection: In an embodiment, the monitoring system 350 isconfigured to detect the presence of the microplate 306 (or other typeof sample support) on the sample carrier 104. If the monitoring system350 determines that the microplate 306 is not present, the monitoringsystem 350 may prevent the sample analyzing apparatus 100 (or certaincomponents of the sample analyzing apparatus 100 that would be affectedby the absence of the microplate 306) from operating. The monitoringsystem 350 may take other actions such as, for example, outputting anaudio and/or visual indication that informs the user of the absence ofthe microplate 306. For these functions, the camera 338 may communicatewith the system controller 190, as described above. In one embodiment,the light source 334 (FIGS. 3 and 4) is utilized. The light source 334is positioned above the region of the sample carrier 104 where themicroplate 306 is intended to be mounted. The light source 334 isactivated to emit the light beam 346 toward this region. The light beam346 may be oriented vertically or an angle to the vertical. The camera338 (or another camera located in a different position in the apparatushousing 128, not shown in FIG. 3) is activated to detect light reflectedfrom a surface of the microplate 306. If the camera 338 detectsreflected light, the monitoring system 350 determines that themicroplate 306 is present. If, on the other hand, the camera 338 doesnot detect reflected light (i.e., detects the absence of a reflectionsignal), the monitoring system 350 determines that the microplate 306 isnot present, and may initiate further actions as described above.

Additionally, the camera 338 may provide images of the regionilluminated by the light source 334. A user may view these images on adisplay screen, in real time or not, and make a manual determination asto whether the microplate 306 is present or absent.

Additionally or alternatively, the monitoring system 350 may beconfigured to detect the presence of the microplate 306 by detecting(measuring) the height of the microplate 306. In the present context,the “height” of the microplate 306 is the position of a part of themicroplate 306 (typically the top surface or top edge of the microplate306) along the vertical axis. The height as a value may be calculatedrelative to any reference datum, such as a point in the apparatushousing 128. If the height detected is lower than a minimum thresholdvalue, the monitoring system 350 may determine that the microplate 306is not present, and may initiate further actions as described above. Forexample, if the microplate 306 is not present, then the height measuredmay be the height of the sample carrier 104 (e.g., the top surfacethereof, or a surface on which the microplate 306 is supported whenpresent), which will be lower than the minimum threshold value. Areference point on the surface of the sample carrier 104 may be definedas corresponding to a plate height of zero. The sample carrier 104 maybe configured as needed to provide a line of sight between the zeroreference point and the light source 334, and a line of sight betweenthe zero reference point and the camera 338.

Monitoring for the presence of the microplate 306 is useful, forexample, in a situation where the user forgets to mount the microplate306 on the sample carrier 104 before initiating samplemeasurement/analysis operations. This monitoring function is especiallyimportant when an injector nozzle 210 or a pipette tip 214 is in use.The injector nozzle 210 or pipette tip 214 could dispense liquiddirectly onto optical components of the sample analyzing apparatus 100and damage such optical components.

Plate height detection: In an embodiment, the monitoring system 350 isconfigured to measure the height of the microplate 306 to determine thatthe height is correct according to a predetermined height specified forthe operation of the sample analyzing apparatus 100. In one embodiment,the light source 334 (FIGS. 3 and 4) is utilized. The light source 334is positioned to emit the light beam 346 toward the top edge of themicroplate 306, thereby creating a light pattern or profile detectableby the camera 338. The detected light pattern may be utilized tocalculate the height of the microplate 306. For example, the systemcontroller 190 may process output signals received from the camera 338,and execute an appropriate algorithm, to calculate the height of themicroplate 306. The monitoring system 350 may also be configured tomeasure the distance between the upper surface of the microplate 306 andcomponents operating proximate to the upper surface of the microplate306 such as, for example, the injector nozzle 210, the pipette tip 214,and the objective lens 218. If the height detected, or the distancebetween the microplate 306 and another component, is lower than aminimum, the monitoring system 350 may prevent the sample analyzingapparatus 100 (or certain components of the sample analyzing apparatus100 that would be affected by this operating condition) from operating.This monitoring function of the monitoring system 350 is useful, forexample, to avoid collisions between the microplate 306 and the injectornozzle 210, the pipette tip 214, the objective lens 218, or othercomponent, thereby preventing damage to such components.

Plate lid presence detection: In an embodiment, the monitoring system350 is configured to detect the presence of a plate lid 326 (FIGS. 3 and4) on the microplate 306. If the use of the plate lid 326 is notprescribed for a particular sample analysis procedure, and themonitoring system 350 detects the presence of the plate lid 326, themonitoring system 350 may prevent the sample analyzing apparatus 100 (orcertain components of the sample analyzing apparatus 100 that would beaffected by this operating condition) from operating and/or initiateother appropriate actions. This monitoring function is useful, forexample, in a situation where the user forgets to remove the plate lid326 before starting the prescribed measurement on the sample. Thismonitoring function is especially important when an injector nozzle 210or a pipette tip 214 is in use. The injector nozzle 210 or pipette tip214 could dispense liquid onto the plate lid 326, and the liquid couldthen flow into contact with optical components of the sample analyzingapparatus 100 and damage such optical components. Similarly, if the useof the plate lid 326 is prescribed for a particular sample analysisprocedure, and the monitoring system 350 determines that the plate lid326 is not present, the monitoring system 350 may initiate appropriateactions in response to such operating condition.

Barcode reading: In an embodiment, the monitoring system 350 isconfigured to operate as barcode reading device to read one or morebarcodes printed on one or more barcode labels 354 (FIG. 3) positionedon one or more sides of the microplate 306 mounted on the sample carrier104. The sample carrier 104 is configured such that when the microplate306 is mounted on the sample carrier 104, a given barcode label 354 canbe adequately illuminated by the light source and light reflected fromthe barcode label 354 can be fully and accurately captured by the cameraso that the barcode can be properly read. For example, the microplate306 may be sufficiently elevated above the top surface of the samplecarrier 104 that large portions of the sides of the microplate 306potentially containing barcode labels 354 are in the lines of sight ofthe light source(s) and the camera(s) utilized for barcode reading. Asanother example, the body of the sample carrier 104 may be structuredwith features (e.g., recesses, openings, etc.) providing or improvinglines of sight with the light source(s) and the camera(s). The lightsource and the camera may be positioned relative to each other such thatthe light beam incident on the barcode label 354 and the light beamreflected from the barcode label 354 are not coincident. In oneembodiment, the light source 330 and the camera 338 (FIGS. 3 and 4) maybe utilized for barcode reading. Additionally, a given microplate 306may have barcode labels 354 on two or more sides of the microplate 306.If it is desired to read such additional barcode labels 354, themonitoring system 350 may include additional light sources and camerasas needed.

Injector monitoring: In an embodiment, the monitoring system 350 isconfigured to monitor the operation of the liquid injecting system,particularly the injector nozzle(s) 210 (FIG. 2) during rinsing andpriming operations of the liquid injecting system. As appreciated bypersons skilled in the art, the fluidic circuitry of the liquidinjecting system, including the injector nozzle 210 and associatedtubing, are typically rinsed and primed in preparation for an injectionoperation, such as the injection of reagents or other liquids onto asample or into a sample container such as the well of a microplate 306.It is desirable to avoid the formation of liquid droplets and liquid-airbubbles on the injector nozzle 210 and nearby tubing. Liquid dropletsand bubbles may contaminate one or more wells of the microplate 306, andmay spill onto the microplate 306 and flow into contact with opticalcomponents of the sample analyzing apparatus 100 and damage such opticalcomponents. Liquid droplets and bubbles also may impair the ability ofthe liquid injecting system to precisely inject predetermined quantitiesof liquid. One or more light sources 330 and 334 and cameras 338 (FIGS.3 and 4) of the monitoring system 350 may be utilized to monitor theinjector nozzle 210 and nearby tubing for the presence of liquiddroplets and air bubbles. In one embodiment, images of the injectornozzle 210 and its surrounding region are acquired by the camera(s) 338and displayed on a display screen, thereby allowing the user to monitorthe injector nozzle 210 and nearby tubing. If the user determines thatliquid droplets and/or bubbles are present, the user may shut downfurther operation of the sample analyzing apparatus 100 so thatappropriate efforts can be made to address the problem.

Pipettor monitoring: In an embodiment, the monitoring system 350 isconfigured to monitor the operation of the liquid pipetting system,particularly the pipette tip(s) 214 (FIG. 2). Pipette tips 214 aretypically removable from the pipettor head of the liquid pipettingsystem so that they can be replaced. During movement and/or use of thepipette tip 214 in the apparatus housing 128, it is possible for thepipette tip 214 to become unsecured and fall from the pipettor head ontothe microplate 306 or other components of the sample analyzing apparatus100, thereby contaminating or damaging such components and/or creatingan obstruction into which other moving components may collide. One ormore light sources 330 and 334 and cameras 338 (FIGS. 3 and 4) of themonitoring system 350 may be utilized to monitor the pipette tip 214 andensure it is securely coupled to the pipettor head, and to detect theevent of the pipette tip 214 becoming separated from the pipettor head.In one embodiment, images of the pipette tip 214 and its surroundingregion are acquired by the camera(s) 338 and displayed on a displayscreen, thereby allowing the user to monitor the pipette tip 214. If theuser determines that pipette tip 214 is not securely coupled or hasfallen away from the pipettor head, the user may shut down furtheroperation of the sample analyzing apparatus 100 so that appropriateefforts can be made to address the problem.

Microplate monitoring for liquid droplets: In an embodiment, themonitoring system 350 is configured to monitor the microplate 306. Inparticular, the monitoring system 350 may be utilized to monitor for thepresence of liquid droplets on one or more surfaces of the microplate306. Such liquid droplets, which may have resulted from operation of theinjector nozzle 210 or the pipette tip 214, may contaminate the samplesor optical components of the sample analyzing apparatus 100. One or morelight sources 330 and 334 and cameras 338 (FIGS. 3 and 4) of themonitoring system 350 may be utilized to monitor the microplate 306 forthe presence of liquid droplets. In one embodiment, images of themicroplate 306 are acquired by the camera(s) 338 and displayed on adisplay screen, thereby allowing the user to monitor the microplate 306.If the user determines that liquid droplets are present on themicroplate 306, the user may shut down further operation of the sampleanalyzing apparatus 100 so that appropriate efforts can be made toaddress the problem.

Microplate monitoring for debugging: In an embodiment, the monitoringsystem 350 is configured to monitor the respective positions and motionsof movable components disposed in the apparatus housing 128 to assist auser in evaluating the operation of the movable components and debuggingany errors found in their positions and motions. As described herein,the sample analyzing apparatus 100 includes various fluidic components,optical components, and mechanical components that are movable in theapparatus housing 128 toward and away from the microplate 306. Thesecomponents include, for example, the injector nozzle 210, the pipettetip 214, the objective lens 218, and the sample carrier 104 on which themicroplate 306 is mounted. Typically for a given sample analysis, thepositions and respective paths of travel along which these componentsmove (and the timing of such movements) are carefully predetermined byprogramming, as may be executed and controlled by the system controller190 (FIG. 2), so that collisions between fluidic/optical/mechanicalcomponents, and between fluidic/optical/mechanical components and themicroplate 306, are avoided. Due to mechanical malfunctions (e.g., in adrive mechanism, a mechanical coupling, etc.), electronics malfunctions(e.g., in an electrical signal path), and/or programming errors (e.g.,in software instructions), it is possible for a component to deviatefrom its intended travel path or from the intended time during which itis move, thereby risking collision with another component. One or morelight sources 330 and 334 and cameras 338 (FIGS. 3 and 4) of themonitoring system 350 may be utilized to monitor one or more suchcomponents, determining whether an error in position or motion exists(or has occurred), debug the error (e.g., repair or replace suchcomponents or electronics controlling such components, fix errors inprogramming, etc.), and subsequently verify that such components areoperating as prescribed. In one embodiment, images of such componentsare acquired by the camera(s) 338 and displayed on a display screen,thereby allowing the user to monitor the components. As part of thisaspect of monitoring, the light sources 330 and 334 and cameras 338 maybe utilized to determine the positions of the components being monitoredsuch as, for example, the heights (positions) of the injector nozzle210, the pipette tip 214, the objective lens 218, and the microplate306, as described above.

In other embodiments, the monitoring system 350 is configured to performany combination of two or more of the foregoing monitoring functions. Byproviding one or a few light sources 330 and 334 and cameras 338, themonitoring system 350 is able to perform a combination of differentmonitoring functions, thereby avoiding the increased cost, complexity,and space requirement that would be associated with providing dedicateddevices to perform such monitoring functions individually.

It will be understood that one or more of the processes, sub-processes,and process steps described herein may be performed by hardware,firmware, software, or a combination of two or more of the foregoing, onone or more electronic or digitally-controlled devices. The software mayreside in a software memory (not shown) in a suitable electronicprocessing component or system such as, for example, the systemcontroller (computing device) 190 schematically depicted in FIG. 2. Thesoftware memory may include an ordered listing of executableinstructions for implementing logical functions (that is, “logic” thatmay be implemented in digital form such as digital circuitry or sourcecode, or in analog form such as an analog source such as an analogelectrical, sound, or video signal). The instructions may be executedwithin a processing module, which includes, for example, one or moremicroprocessors, general purpose processors, combinations of processors,digital signal processors (DSPs), application specific integratedcircuits (ASICs), or field-programmable gate arrays (FPGAs). Further,the schematic diagrams describe a logical division of functions havingphysical (hardware and/or software) implementations that are not limitedby architecture or the physical layout of the functions. The examples ofsystems described herein may be implemented in a variety ofconfigurations and operate as hardware/software components in a singlehardware/software unit, or in separate hardware/software units.

The executable instructions may be implemented as a computer programproduct having instructions stored therein which, when executed by aprocessing module of an electronic system (e.g., the system controller190 shown in FIG. 2), direct the electronic system to carry out theinstructions. The computer program product may be selectively embodiedin any non-transitory computer-readable storage medium for use by or inconnection with an instruction execution system, apparatus, or device,such as an electronic computer-based system, processor-containingsystem, or other system that may selectively fetch the instructions fromthe instruction execution system, apparatus, or device and execute theinstructions. In the context of this disclosure, a computer-readablestorage medium is any non-transitory means that may store the programfor use by or in connection with the instruction execution system,apparatus, or device. The non-transitory computer-readable storagemedium may selectively be, for example, an electronic, magnetic,optical, electromagnetic, infrared, or semiconductor system, apparatus,or device. A non-exhaustive list of more specific examples ofnon-transitory computer readable media include: an electrical connectionhaving one or more wires (electronic); a portable computer diskette(magnetic); a random access memory (electronic); a read-only memory(electronic); an erasable programmable read only memory such as, forexample, flash memory (electronic); a compact disc memory such as, forexample, CD-ROM, CD-R, CD-RW (optical); and digital versatile discmemory, i.e., DVD (optical). Note that the non-transitorycomputer-readable storage medium may even be paper or another suitablemedium upon which the program is printed, as the program can beelectronically captured via, for instance, optical scanning of the paperor other medium, then compiled, interpreted, or otherwise processed in asuitable manner if necessary, and then stored in a computer memory ormachine memory.

It will also be understood that the term “in signal communication” asused herein means that two or more systems, devices, components,modules, or sub-modules are capable of communicating with each other viasignals that travel over some type of signal path. The signals may becommunication, power, data, or energy signals, which may communicateinformation, power, or energy from a first system, device, component,module, or sub-module to a second system, device, component, module, orsub-module along a signal path between the first and second system,device, component, module, or sub-module. The signal paths may includephysical, electrical, magnetic, electromagnetic, electrochemical,optical, wired, or wireless connections. The signal paths may alsoinclude additional systems, devices, components, modules, or sub-modulesbetween the first and second system, device, component, module, orsub-module.

More generally, terms such as “communicate” and “in . . . communicationwith” (for example, a first component “communicates with” or “is incommunication with” a second component) are used herein to indicate astructural, functional, mechanical, electrical, signal, optical,magnetic, electromagnetic, ionic or fluidic relationship between two ormore components or elements. As such, the fact that one component issaid to communicate with a second component is not intended to excludethe possibility that additional components may be present between,and/or operatively associated or engaged with, the first and secondcomponents.

It will be understood that various aspects or details of the inventionmay be changed without departing from the scope of the invention.Furthermore, the foregoing description is for the purpose ofillustration only, and not for the purpose of limitation—the inventionbeing defined by the claims.

What is claimed is:
 1. A sample analyzing apparatus for performing anoptical-based measurement on a sample, the sample analyzing apparatuscomprising: a housing; a first light source disposed in the housing andconfigured for generating excitation light; excitation optics disposedin the housing and configured for directing the excitation light fromthe first light source to the sample disposed in multi-well microplate,wherein the sample emits emission light in response to being irradiatedby the excitation light; a first light detector disposed in the housingand configured for measuring the emission light emitted by the sample inresponse to being irradiated by the excitation light; emission opticsdisposed in the housing and configured for directing the emission lightfrom the sample to the first light detector; one or more liquid handlingcomponents configured to deliver liquid to the sample disposed in themulti-well microplate; and a monitoring system configured for monitoringan area of the housing in which one or more movable components arelocated, the area corresponding to a space in which the one or moreliquid handling components are configured to periodically interact withthe sample disposed in the multi-well microplate, the monitoring systemcomprising: a second light source disposed in the housing and configuredfor illuminating the one or more movable components; and a second lightdetector disposed in the housing and configured for detecting lightreflected from the one or more movable components in response to beingilluminated.
 2. The sample analyzing apparatus of claim 1, wherein themonitoring system is configured for detecting an operating condition ofthe one or more movable components.
 3. The sample analyzing apparatus ofclaim 2, wherein the operating condition is selected from the groupconsisting of: the presence of the one or more movable components in thehousing; a position of the one or more movable components in thehousing; a distance between a first movable component of the one or moremovable components and a second movable component of the one or moremovable components disposed in the housing; the presence of liquiddroplets or bubbles on the one or more movable components; a path alongwhich the one or more movable components is moving in the housing; and acombination of two or more of the foregoing.
 4. The sample analyzingapparatus of claim 2, wherein the monitoring system is configured forshutting down an operation of the sample analyzing apparatus, inresponse to detecting the operating condition.
 5. The sample analyzingapparatus of claim 1, wherein the monitoring system is configured forreading a barcode on a barcode label disposed in the housing.
 6. Thesample analyzing apparatus of claim 5, wherein the barcode label isdisposed on a sample support disposed in the housing.
 7. The sampleanalyzing apparatus of claim 1, wherein the one or more movablecomponents comprises a sample support configured for supporting thesample, and the monitoring system is configured for detecting thepresence of the sample support in the housing.
 8. The sample analyzingapparatus of claim 1, wherein the one or more movable componentscomprises a sample support configured for supporting the sample, and themonitoring system is configured for measuring a position of the samplesupport relative to a reference point in the housing.
 9. The sampleanalyzing apparatus of claim 1, wherein the one or more movablecomponents comprises a sample support configured for supporting thesample, and the monitoring system is configured for detecting thepresence of lid mounted on a top surface of the sample support.
 10. Thesample analyzing apparatus of claim 1, wherein the one or more movablecomponents comprises a sample support configured for supporting thesample, the sample analyzing apparatus further comprises an additionalcomponent disposed in the housing, and the monitoring system isconfigured for measuring a distance between the sample support and theadditional component.
 11. The sample analyzing apparatus of claim 10,wherein the additional component is selected from the group consistingof: an injector nozzle; a pipette tip; and an optical lens.
 12. Thesample analyzing apparatus of claim 1, wherein the one or more movablecomponents comprises a sample support configured for supporting thesample, and the monitoring system is configured for detecting thepresence of liquid droplets on the sample support.
 13. The sampleanalyzing apparatus of claim 1, wherein the one or more movablecomponents comprises a fluidic component configured for dispensingliquid to the sample, and the monitoring system is configured formeasuring a position of the fluidic component relative to a referencepoint in the housing.
 14. The sample analyzing apparatus of claim 13,wherein the fluidic component is selected from the group consisting of:an injector nozzle; and a pipette tip.
 15. The sample analyzingapparatus of claim 1, wherein the one or more movable componentscomprises the one or more liquid handling components, and the monitoringsystem is configured for detecting the presence of liquid droplets orbubbles on the one or more liquid handling components.
 16. The sampleanalyzing apparatus of claim 1, wherein the one or more movablecomponents is a pipette tip associated with the one or more liquidhandling components, the pipette tip configured for being coupled to andmovable by the one or more liquid handling components, and themonitoring system is configured for detecting whether the pipette tiphas been decoupled from the one or more liquid handling components. 17.The sample analyzing apparatus of claim 1, wherein the second lightdetector is a camera configured for acquiring images of the movablecomponent.
 18. The sample analyzing apparatus of claim 17, comprising asystem controller communicating with the camera, and configured forcontrolling presentation of images acquired by the camera on a displayscreen external to the housing and viewable by a user.
 19. The sampleanalyzing apparatus of claim 17, comprising a system controllercommunicating with the camera, and configured for controlling playbackof video images acquired by the camera on a display screen external tothe housing and viewable by a user.
 20. A method for monitoring amovable component of a sample analyzing apparatus, the sample analyzingapparatus comprising a housing in which the movable component isdisposed, a first light source disposed in the housing and configuredfor generating excitation light, excitation optics disposed in thehousing and configured for directing the excitation light from the firstlight source to a sample disposed in multi-well microplate, a firstlight detector disposed in the housing and configured for measuringemission light emitted from the sample in response to being irradiatedby the excitation light, and emission optics disposed in the housing andconfigured for directing the emission light from the sample to the firstlight detector, one or more liquid handling components configured todeliver liquid to the sample disposed in the multi-well microplate themethod comprising: operating a monitoring system to monitor the movablecomponent by: operating a second light source disposed in the housing toilluminate the movable component; and operating a second light detectordisposed in the housing detect light reflected from the movablecomponent in response to being illuminated.
 21. The method of claim 20,wherein operating the monitoring system comprises performing anoperation selected from the group consisting of: operating the secondlight source and the second light detector to detect the presence of themovable component in the housing; operating the second light source andthe second light detector to detect a position of the movable componentin the housing; operating the second light source and the second lightdetector to calculate a distance between the movable component and anadditional component disposed in the housing; operating the second lightsource and the second light detector to detect the presence of liquiddroplets or bubbles on the movable component; operating the second lightsource and the second light detector to monitor a path along which themovable component is moving in the housing; operating the second lightsource and the second light detector to read a barcode on a barcodelabel disposed in the housing; and a combination of two or more of theforegoing.